The official Xinhua news agency said Wednesday night that police detained five suspects in connection with the crash about 10 hours after it occurred, adding that the three occupants of the car — all of whom died — were a man named Usmen Hasan, his wife and his mother. From the WSJ’s report:

The crash, which occurred in front of the Forbidden City in Beijing’s Tiananmen Square, also killed two tourists and injured 40 others, according to authorities.

Beijing police recovered gasoline canisters, iron rods, two meat cleavers and banners with extremist slogans from the vehicle used in the attack, Xinhua said. Police identified the vehicle used in the attack as a Jeep with a license plate from the western region of Xinjiang, Xinhua said.

Xinjiang is home to the mostly Muslim Uighur minority, some of whom have been engaged in a sometimes violent separatist campaign for decades, but there hasn’t been an attack in Beijing since the late 1990s. Tensions between Uighurs and Han Chinese have occasionally exploded inside Xinjiang itself, including in 2009, when ethnic riots in the Xinjiang capital of Urumqi left nearly 200 dead.

While China’s Internet monitors often delete posts critical of the regime, the social media censorship in this case may have been designed to prevent ethnic tensions from rising in the capital. On Chinese WSJ’s feed on the Twitter-like Sina Weibo account, censors removed more than 20 comments in less than 10 minutes.

Comments left on the Journal’s feed and that of China’s state broadcaster were largely devoid of ethnic references. And while many called for the government to crack down hard on terrorism, a handful revealed flickers of doubt.

“Taking your family along on a suicide attack — there’s got to be more to this story,” wrote one user.

“Are you certain it’s a terrorist attack?” wrote another.

Yet another cautioned others not to make let the incident color their view of Uighurs. “One group of people from Xinjiang doesn’t represent an entire ethnic group,” the user wrote. “Don’t go looking at the Uighur people with colored lenses because of a single incident.”

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